One-step pre-column derivatization method for HPLC-UV determination of organic acids in fruit juices

Abstract

A simple and effective one-step pre-column derivatization method for reversed-phase HPLC-UV determination of the major organic acids (citric, malic, tartaric, and succinic acids) in fruit juices has been developed. The method is based on the coupling reaction of organic acids with 1-naphthylamine in the presence of N,N′-diisopropylcarbodiimide. The resulting organic acid amide derivatives were successfully separated on an AQ-C18 column and detected by a UV detector at 222 nm. Isocratic elution was performed using an acetonitrile-methanol-tetrahydrofuran-water (37:4:1:58; v/v) mixture as a mobile phase at a flow rate of 2.0 mL/min. Validation studies showed good recoveries ranging from 88.97 to 92.52% with RSD % between 2.95 and 4.56%. The detection limits obtained were 0.18, 0.48, 0.14, and 0.69 µg/mL for tartaric acid, malic acid, succinic acid, and citric acid, respectively. The method was successfully applied to three different commercial fruit juice and nectar samples with little or no clean-up procedures.

Graphical Abstract

Keywords:

• Derivatization
• HPLC-UV
• 1-naphthylamine
• N,N′-diisopropylcarbodiimide
• organic acids

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This study was supported by Ondokuz Mayis University Scientific Research Projects under Grant (PYO.FEN.1904.20.008).